# Codex4 - For Serious Study

> For serious language learners

Canonical page: [https://chrome-stats.com/d/id6743228019](https://chrome-stats.com/d/id6743228019)

## Overview

- **ID:** `id6743228019`
- **Platform:** Apple
- **Type:** Apple app
- **Status:** Available
- **Publisher:** Jonas Richner
- **Category:** Education
- **Rating:** 5.00 / 5 (2 ratings)
- **Version:** 3.66
- **Last updated:** 2026-04-14
- **First published:** 2025-05-29
- **Size:** 52 MB
- **Data as of:** 2026-09-20
- **Store listing:** [Apple App Store](https://apps.apple.com/us/app/codex4-for-serious-study/id6743228019)
- **Website:** [https://codex4.com](https://codex4.com/)
- **Privacy policy:** [https://codex4.com/privacy-policy/](https://codex4.com/privacy-policy/)

## Description

Get fluent faster by learning the words you actually use.

Codex4 helps you build a usable vocabulary and keep it for the long term.

- Learn what you need: Add your own words from any text in one tap. Build vocabulary for your job, studies, or hobbies.
- Retain more with less effort: Reviews are timed by FSRS (a modern spaced-repetition model) so you study exactly when it counts.
- Master real usage: The app treats each word as a lemma, so forms and conjugations are covered naturally as you progress.
- Stay organized and motivated: Clear stats show what’s due, what’s known, and what’s next.
- Bring any content: Automatic word extraction and a context-aware lemmatizer handle homonyms and multi-word phrases.
- Your data stays yours: Keep access to review even after unsubscribing, and export your words and learning data anytime.

- No gimmicks: Fast sessions, clean design, built for serious learners.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

## Rankings

- #672,196 — Overall

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Source: [Chrome-Stats](https://chrome-stats.com/d/id6743228019)